# Issues encountered with grid output in the 0.3.1 version

**URL:** <https://bempp.discourse.group/t/issues-encountered-with-grid-output-in-the-0-3-1-version/284>\
**Category:** Applications\
**Created:** [20 September 2024 09:00 UTC](https://bempp.discourse.group/t/issues-encountered-with-grid-output-in-the-0-3-1-version/284 "2024-09-20T09:00:33Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![S.L](https://avatars.discourse-cdn.com/v4/letter/s/e274bd/32.png) [@S.L](https://bempp.discourse.group/u/S.L)\
**Post date:** [20 September 2024 09:00 UTC](https://bempp.discourse.group/t/issues-encountered-with-grid-output-in-the-0-3-1-version/284/1 "2024-09-20T09:00:33Z")

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Hello! I am delighted to have discovered bempp as an invaluable aid for my computations.  
But, when using 0.3.1, upon completing calculations and attempting to export the grid, an error is encountered:

Running this operation:

```auto
bempp.api.export('test1.msh', grid_function=boundary_fun)

```

An error is reported:  
_AssertionError: Incompatible cell data. 1 cell blocks, but ‘real’ has 342 blocks._

Then I try 0.2.4, and 0.2.4 successfully outputs the test1.msh file, I’m wondering if the new version introduces additional control parameters that might affect this. If so, could you please inform me? Thank you.

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<div class="post-metadata">

**Author:** ![tchoum](https://avatars.discourse-cdn.com/v4/letter/t/dc4da7/32.png) [@tchoum](https://bempp.discourse.group/u/tchoum)\
**Post date:** [23 September 2024 11:02 UTC](https://bempp.discourse.group/t/issues-encountered-with-grid-output-in-the-0-3-1-version/284/2 "2024-09-23T11:02:11Z")

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Hey, if you pass the _transformation_ argument, it should work properly.

For example:

```auto
bempp.api.export('test1.msh', grid_function=boundary_fun, transformation="real")

```

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<div class="post-metadata">

**Author:** ![S.L](https://avatars.discourse-cdn.com/v4/letter/s/e274bd/32.png) [@S.L](https://bempp.discourse.group/u/S.L)\
**Post date:** [24 September 2024 03:35 UTC](https://bempp.discourse.group/t/issues-encountered-with-grid-output-in-the-0-3-1-version/284/3 "2024-09-24T03:35:29Z")

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Thank you for your assistance, it works!